An Afghan insurgent faction has reportedly voiced its backing for construction of a multibillion-dollar pipeline through Afghanistan to take Turkmen gas to India and Pakistan.

Hezb-i Islami, an insurgent force led by former prime minister Gulbuddin Hekmatyar, was said to have announced its full backing for the so-called TAPI pipeline project on December 18 and volunteered to help protect it.

Turkmenistan, Afghanistan, Pakistan, and India this month signed a preliminary agreement to push ahead with the pipeline.

Hezb-i Islami does not control most of the proposed route, which runs through the Taliban heartland in southern Helmand and Kandahar provinces.

The government says it would bury the pipeline up to two meters underground there to ensure its safety.